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bigdazzler
11-07-2009, 8:25pm
This may be a silly question but you never learn unless you ask ...

With a manual flash .. is each power increment say from 1/32th , 1/16th , 1/8th , 1/4, 1/2 , 1/1 .. are each of these intervals equivalent to 1 stop ??

Empire
11-07-2009, 9:57pm
Its 1/3 stops mate (assuming its the same as the canons)

jev
11-07-2009, 10:34pm
Its 1/3 stops mate (assuming its the same as the canons)

No, that is not what is asked, the question is on the light output of the flash not the clicks in your camera. Check the list in the back of the manual of your flash (this one is for the 580EX):
http://www.ausphotography.net.au/gallery/files/1/5/2/3/guide_numbers.jpg
As you can see, power x 2 = guide number x √2. Since guide number = aperture x distance, if you double the power, you gain 1 stop. Or, each time you half the power, you loose one stop. So, yes, each interval on the flash is one stop.

MarkChap
11-07-2009, 10:35pm
Yes Darren you are correct

1/1 -> 1/2 is 1 stop less light 1/2 -> 1/4 is 1 stop

The canon speed lights make those adjustments in 1/3 stop increments
EG :- 1/1 -> 1/2 goes 1/1, -1/3, -2/3, 1/2, -1/3, -2/3, 1/4 etc

Onya Jev, got in before me and explained it better, :th3:

TOM
11-07-2009, 11:01pm
Dazza, sorry just got your pm a minute ago. have sent one.

bigdazzler
12-07-2009, 1:03am
Thanks guys .. thought as much but wanted to be certain.

Empire
12-07-2009, 2:37pm
Sorry I misundertsood the Q, I was thinking the increments in manual mode are at 1/3 stops as opposed to are those 1 full stop. My bad.